Pulverizing mill



April 3o,` 1929. y

7 R., SQ RILEY PLvERIzING um.

Filed Jan 5, 1924 4 VSheets-Sheet 7 1 ATTO EYJ.

April 30, 1929` R.' s. RILE-v 1,711,063

PULvE'RIzING MILL Filed Jan. s, 1924 .4 Sheets-Sheet 3 mms/TOR.'

5055er R/LLY Patented Apr.` 30, i

4PA'IE-15Vr OFFICE.

UNITED STATES i EoEEnT s. RILEY, or -woEcEsTE-n, mssAcnbsETTs, saumon Tosam-ono EILEY sToxEE coMrANY, oir woEcEsTEE, MASSACHUSETTS, AoonToEATIoN or las SACHUSETTS.

r'ULvEEIzING u1u..

Application medianuaryys, im. smal no. ascesi.

' This invention relates to a mill for'pulverizin dry coal, cement orother material of simi ar structure. rThis mill is designed -forcontinuous operation, with automatic 5 feed of the coarse materialto oneend of the mill and continuous delivery of the pulverized product fromthe other end of the mill.

One object of my invention relatesl to the provision of improved devicesfor producing l the pu'lverizing action and particularly to an improvedconstruction 'of roll hammer-for use in such a machine, thisl hammerhaving both a roller and a ball-action. I have also j provided anindicating device by means of l which the position of the roll hammersrelai tive to the tread orv bull ring may be observed duringtheoperation of the machine.

A veryimportant feature of the invention lies in the particularconstruction of the bull ring, the conical convergingr walls of whichare effective to feed the material under the hammers and thus enable themachine to operate without the kuse' of the customary plows,savino' muchpower 7and expense. j

Another object of my invention is to provide an improved mechanicalseparatingidevice at the discharge end of the mill by means of which thecoarser particles Vof material may be separated from the fine pulverizedparticles and may be returned tothe mill for further reduction. s.

Another feature of my invention relates to the provision of an improvedseparator of the gravity type which will return any remaining coarseparticlesor tailings to the hopper from which the machine is fed. In

the Vpreferred form, the operation of thisV gravity separator may beadjusted andcontrolled by regulating devices'to be described.

I have also provided an improved form of hopper, having provision foradjustment, of

the feed without change in the rate of actuation thereof.

In a modified form of my invention, I have shown a machine in which asupplemental pulverizing agency is provided, acting -upon the materialafter it has passedthrough the roll hammer 'mechanism and serving as asubstitutel for the mechanical separating device above referred to. My`invention further relates to arrangementsand 'combinations of partswhich will be hereinafter describedand more particu- )arly pointed outin the` appended claims.

A preferred form of the invention is shown in the drawings in whichFig.' 1 is a longitudinal sectional elevation of my improved machine; nFig. 2 is an end elevation thereof, looking in the direction of thearrow 2 in Fig. 1;

Fig. 3 is a sectional elevation` of one of the roll -hammers and itssupport;

Fig. 4 is a transverse sectional elevation, taken along the line 4--4 inFig. 3 and showing'the spider or support for the ball ham-V mers;

Fig. 5 is a perspective view of the mechanical separating device;

Fig. is a diagrammatic plan view of c ertain driving connections;

Fig. 7 isa sectional end elevation of the l hopper and feedingdevice;Fig. 8 is a partial longitudinal sectional? elevation of ther same partsFig. 9 is'a detail plan view of the hopper ad] usting mechanism; and

' Fig. 1.0 is a artial sectional side elevation showing a ino itedconstruction.'

Referring particularly to Figs. -1 and 2, I.

have shown a pulverizing mill comprising va casing 10 within which isrotatably mount ed an annular rotatable member 11 having-a gear 12formed on its outer face. The member 11 rotates in fixed bearings 13 andacts as a support :for a bull ring 14. The ring 14 and member 11 haveco-operating tapered -contact surfaces and the ring 14 is securely heldto its seat in the member 11 by ahead 16 bolted to the side of themember 11 and having clamping screws 17 threaded therein and engagingthe larger end of the bull rin 14.

A plurality of roll hammers 20 are rotatably mounted upon arms 21 (Fig.3) which in turn are pivoted at 24 to a frame or spider 25 keyed orotherwise secured to a drive shaft 26. The frame 25 isprovided withpairs of spaced arms or projections forming sepa.

rated bearings for the arms 21,.as clearly iii- `dicated in Fig. 4. Uponthe face adjacent the rolls, the frame 25 is provided with inclined ribs27 which strengthen the bearing arms and act to assist the -feed ofmaterial.

Each roll 20 has an end ring-30 secured thereto by screws or Vbolts 31and providing an annular recess for a collar 32 fixed to its arm 21 by atapered pin 33. Each roll 20 is also preferably provided with a bushing,

or bearing sleeve 34 and suitable provision is made for introducinglubricant to' the bearing through an oil assage in the arm 21. A shield36 exclu es coal or other material from the bearings of the arms 21.

An indicator arm'37 is fixed to one of the roll hammer arms 21 andextends toward the axis of the shaft 26. A rod 38 is slidable in agroove 39 in the shaft 26 andextends beyond the right hand end of theshaft, as shown in Fig. 1. A pointer 40 may be provided on the casing10l of the driving mechanism and the end of the rod 38 maybe graduatedas indicated at 41. A glance at these graduations will indicateaccurately the position of the roll hammers with reference to the bullring at any time during the operation of the machine.

The axis of the drive shaft 26 is preferably offset downwardly from theaxis of tht` member 11 and gear 12, for a purpose to be described.

Any suitable .driving means may be\pro vided for rotating the ringsupporting member 11 and the roll hammer supporting frame 25. As shownherein, the shaft 26 is provided With a gear 42 (Figs. 1 and 6) engagedby pinion 43 mounted on a counter shaft 44 having a pinion 45 meshingwith a gear 46. The gear 46 vis fixed to a second counter shaft 47having a pinion 48 which drives the ring gear 12 previously described.Shaft 44 may be driven by an electric convenient manner` l motoror inany other A hopper 50 (Figs. 1 and 7) is provided `for feedinv thecoarse material to the pulverizino' mill. The hopper may be connected byapipe 51 to any suitable storage space from which a sup ly of rawmaterial may be conveniently received. The hopper 50 has an offset-discharge opening 52 (Fig. 7) and e has a feeding device 53 rotatablymounted between the hopper and the discharge opening 52. The feedingdevice 53 is mounted upon a shaft 54 to the end of which is secured aratchet` ring or cog wheel 56 with which a pawl 57 is intermittentlyengaged.

' The pawl 57 is mounted upon a feed lever 58 (Fig. 2) connected by alink 59 to a pin 60 eccentrically mounted in a gear 61 engaged anddriven by a pinion 62 on the shaft 26.

Through these connections, the feeding de- I vice 53 in the hopper 50 isangularly advanced with a relativelyslow intermittent movement. Thefeeding device 53 has a plurality of axial feeding blades 63 (Fig. 7). As the vblades -63 rotate past an vopening .64 in the side of the hop er50, the recesses between the blades are lilledwithcoal or othermaterial, which is carried around' by the blades and is dischar edthrough the opening 52.

It is often esirable toclian' e the rate of feed of material tothe millwlthout changing the gear connections to the crank gear leand for thispurpose I have provided the the shaft 54,

conical part of the a series of four blades 81 arrangedaxia the drivingshaft 26 and extending radially members 66 at one end thereof. One ofthe members 66 extends between each two adjacent blades 63 `of thefeeding device 53.

-These members 66 are `closed at their'outer or segmental faces, so thatthey complete a desired portion of the cylindrical surface of thefeeding device and leave no recess in such portion to receive materialas the blades 63 rotate 'past the opening 64. Suitable meansi's-provided for adjusting the sleeve and the adjusting member V66axially of nuts 67 (Fig. 9) threaded on rods 68 fixed in the hoppercasing' 50. 4 The nuts 67 are grooved orllanged and fit between theupper and lower lparts of a plate 69 which acts as a yoke for a groovedend portion 70 of the., sleeve 65. By turning the nuts 67 the sleeve beadjusted axially. V- With this construction, the length of the 65 andmembers 66 Vmay recesses in the feeding device may be varied Vtoincrease 0or"decrease the capacity of the feeding device at eachintermittent actuation thereof. 4

A blade 72 (Fig. 7) is secured in the hopper-50 and tends to break upadhering masses of coal as they enter the hopper and to cause siron orother heavy material to pieces of fall to a recess or pocket 7 3 formedbelowr the such means comprising wing feeding opening 64 and welladapted to rel ceive such heavy material. A cap or'plate 74 closes anopening 75 through which the material' collected in the pocket 73 may beremoved.

The material fed fromthe hopper passes downward in the' casing 10` andis gradually fed to the bull ring past thespider 25. The hammers 20 havea combined roller and ball action on the'material. The straight line orhammer is preferabl at a slight angle to the adjacent surface o the bullring, so that the coal isxsubject to an increasing crushing action asVit is advanced across the ring. The rounded or ball portion of thehammer then has a pulverizing action similar to the usual ball mill.

As the coal or other material is ground or ulverized between the balls2() and the bul ring 14, the fine pulveriz'cd material is drawn througha' discharge opening 75 in the casinglO into a gravity separator 76 withwhichis connected 'a suitable.4 exhaust -fan (not shown).

As the material is dravvmtovvard the-dis i charge opening, it passes afan-like mechanical separator or rejector 80, most' clearly shown inFig. 5. The rejector 8O com rises ly of ,from the axis. Upon the leadingface of each of the blades 81 there is provideda guide 0r llO flan e 83which is inclined toward the axis of t e shaft 82 in the direction oftheV dis# chargel opening 5.

As the pulverized material passes through the fan-like rejector 80, theline material asses freely along into the gravity separator coursethrough the gravity separator 76 which has an outer casing 85 and aninner conduit-86 having an extension 87 communicating with v lthe hopper50. A swinging check'valve 88 permits downward movement yof material.lthrough the extension 87' but prevents entrance of air in the oppositedirection.

` A discharge pipe 90 at the top of the casing A is connected tosuitable exhaust mechanism (not shown) as previously stated. The pipehas a sleeve 91slidably mountedthereon, with its lower end extendingbelow the upper end ofJt-he conduit 86. Adjusting screws 92 are providedby which the sleeve 91 may be raised or lowered to vary the projectionof the sleeve into the conduit 86.

As the pulverized material is drawn upward through the ravity separator76, it necessarily follows t el direction of the arrows a in Fig. 1,passing over the upper'end of the con- .duit and downward around thelower end of lthe sleeve 91. As the direction of movement is reversed,the heavier particles fall into the conduit 86 and are delivered bygravity to the hopper 50,'while the lighterparticles pass upward to thedischarge pipe 90.

Suitable packing rings 95 and 96 (Fie. 1)

are provided to prevent escape of the pu verized material during its-passage through'the mill. An annular pocket 97 is formed at the righthand end of the bull ring 14, within which articles of iron and otherheavy material may conveniently collect. A ring or clinedsurfaces isvery important.

of the conical orincllned surface -on the enflange 98 on the shaft 26forms an inner limit or stop for the hammers 20.

The inner face of the bull ring 14 is formed with two oppositelyinclined or conical surfaces and the effect of these oppositely in- Theaction traneeside, assisted by' centrifugal force, is to` Y feed thematerial forward under the roll ham# mers, while the action of thesecond inclined' surface is to reverse the feed of the coarserparticles, returning them under the hammers, while the inermaterialpasses along to the rejector 80.

, In Fig.

pplveriz'ingand rejecting device is provided tween the' bull ring 14 andthe lower end of place.

10, I have shown a slightly modified form of my invention `in which acombined` the gravity. separator 76. This device comprises a disc 100mounted upon an independently rotated shaft 101 and aving a series ofpins 102 fixed in the left hand face thereof, alternating with pins 103fixed. in a casing member 104. v

As the 'pulverized material. leaves the hammers, it is drawn around theouter edge of the disc 100 as indicated by the arrow b in Fig. 10

and is then drawn inward pastvthe pins 102 and 103 to the dischargeopening 105 at whichl point it is delivered to the. gravity separatorHaving thus described my nvention, it is believed that the operationwill beclearly apparent. supply of suitable'material isfed to the hopperV50 through the feed pipe 51 or in any Vother .convenient manner andthe-material' is intermittently fed `from the hopperfin measuredquantities to the roll hammers and bull ring which are preferablyrotated asdescribed 1n opposite directions. The rolls-20 are free toturn upon their supporting pins 4and in Contact with' the bull rmg andare swung strongly outward by centrifugal force. The outer wall of theroll portion of each hammer is inclined relatively to the adjacentconical. wall of the bull ring, so that the material as it advancesissubject to an increasing crushingaction, but the roll wall and ringare out of direct Vcontact in this ortion of the mechanism.` Thematerial is ed forward by the combined ei'ect of centrifugal force andthe outwardly inclined tread of the bull ring.

The return of the coarser particles under the hammers has been already,explained.

`As the material is pulverized, it first passes the rejector 80- whichturns back the coarser particles for` further treatment. The linerparticles .pass to the gravity separator 76 where further separation bygravity takes The coarse particles or tailin sepa- Y rated at this pointare returned to t4 e hopper for further reduction.

The combined crushing and pulverizing ac- I tion Yof 'the hammers 20 hasbeen fully described. By offsetting the axis of rotation of the spiderand hammers relatively to the bull ring or tread 14, the effect ofgravity on the hammers is vsubstantially balanced by the increasedcentrifugal action at the longer rad-ius and the pressure of the hammerson'the material islar ely equalized.

Having t us described my invention and the advantages thereof, Ido notwish to be limitedto the details herein disclosed otherwise than assetforth in the claims, but what I -said ring',a rotatable member,

Y tively rotate said member, said hammers hav- `ing' ball shaped outerends and` straight/ line Y portions associated therewith, the ring andmember being driven-continuously inoppo- Site directions. i

2. A Yulverizing mill having, in combination, a ull ring, means topositively rotate said ring, a- Arotatable ,membeig a plurality of rollhammers rotatably and pivotally connected to saidmember, and means topositively rotate said member, said hammers havingball shaped outer endsand having straight line roll surfaces slightl inclined to the adjacentinner face of the b ring when swung outward to approximate engagementtherewith, the ring and member being driven continuously in oppositedirections.

Y3. A pulverizing mill having, in combination, a bull ring, means topositively rotate said ring, a rotatable member, a plurality of rollhammers rotatably`r and pivotally conand means to positively rotate saidmember, said hammers having ball shaped ends and straight line rollersurfaces slightly inclined to said 'bull ring,

whereby to crush and pulverize'the material with an increasing crushingroller action at the entrance side of the ring and with a ballpulverizing action at the dischargefside of the ring. v

4. In a pulverizing mill, a rotating mem-- ber, swinging arms mountedthereon, rotatable crushing devices on said arms, and means to indicatethe radial position of said devices.

5. In a pulverizing mill, a rotating member, swinging arms mountedthereon, rotatable crushing devices on said arms, a shaft'on which saidmember is mounted, an indicating rod slidable axiallv of said shaft, andconnections from said rod to said swinging arms.

6. vIn a pulverizing mill, a bull ring, and meanst positively rotatesaid ri tatingmember, a plurality of roll hammers each individuallyrotatable and pivotally mounted to swing on said member, and means torotate said member, the axis of rotation of said member being out ofalignment with the axis ofsaid ring.

7In s. pulverizing mill, a bull ring, and means to positively rotatesaid ring, a rotating member, a plurality of roll hammers eachindividually rotatabler and pivotally mounted to swing on said member,and means to rotate said member, the axis of rotation of saidmember'being positioned. slightly belowthe axis of said ring.

' 8. pulverizlng mill having, in combinaand means to tion, a bull ring,means to positively rotate -ing roller action at the entrance side ofthe ring and with a ball pulverizing action at the discharge side of thering, the bull ring being always out of direct Contact with the hammersin the roller portions thereof.

9. A pulverizing mill having, in combination, a bull ring, means topositively rotate said ring, a rotatable member, a plurality of hammersmounted thereon for substantially radial operative movement, and meansto rotate said member, said bull ring having a conicl'alsurfaceco-operat-ing with centrifugal orcetofadvance the material towardthe centralportion of the tread, the bull ring and member being `drivencontinuously in opposite directions. Y

l0. A pulverizing mill having, in combination, a bull ring, means topositively rotate said ring, a rotatablemember, a plurality of coneshaped hammers mounted vthereon for substantially radial operativemovement, and a rotor to rotate Said member, said bull ring .having aconical surface co-operating with centrifugal force' to return coarserparticls from the crushed material toward the central port-ion of thetread, the cone portion of the hammers and the ring being angularlyspaced from each other.

11. A pulverizing mill having, in combination, a bull ring, meanstopositively rotate said ring, a rotatable member, a plurality of coneshaped hammers mounted thereon for substantially radial operativemovement, and

means to rotate said member, said bull ring having oppositely disposedconical surfaces co-operating with centrifugal force to feed thematerial toward-the central portion of the tread, and the ring beingangularly spaced Yfrom each other. 1

12. A pulverizing mill comprising abull ring, a rot-ating member, aplurality of roll hammers movably mounted on said member,

said member, said hammers each comprising a ball shaped end and astraight side roll portion, the roll portion of tion of their lengthwhen in crushing relation.

13. A pulverizing converging and relathe. cone portion of the hammerssaid hammers beingv positioned at al slight angle to the adjacent treadQf said ring, and thus providing a out of direct contact',

apparatus comprisinga casing having an inletfor coarse material andanoutlet for the n'ely pulverized inapositively rotate lsaid ring and YCah terial, a bull ring and rolls associated therewith near the inletfor pulverizing the coarse particles, and rapidly revoluble impactmembers arranged in the path of the material traveling from the firstzone to the outlet which are arranged to finely pulverize the materialted thereto. v

14.-. A pulverizing apparatus comprising a casing provided with an inletand an outoutlet.

let respectively on opposite sides thereof, means forming twopulverizing zones connected by an annular passage, means in the,

pact members in' the second chamber arranged to finely pulverize thematerial as it passes to the outlet.

16. A pulverizing apparatus comprising a casing having an inletV and acentrally located outlet on Aopposite sides thereof, means forming'twopulverizingzones connected by an annular passage, means includingyieldable, pivotally mounted crushing members arranged in the rst zoneadjacent to the inlet for preliminarily crushing the material, andrevoluble impact members on the rotor' and stationary impact lmemberswhich are located on the casing'in'the second zone near the outlet andserve to linel pulverize the material as it travels inwar 17. Apulverizing' apparatus comprising a casing having an inlet andacentrally located outlet on opposite sides thereof, .means forming twopulverizing zones connected by an annular passage, 'means includingyieldable, pivotally mounted revoluble members in the irstzone adjacentto the inlet to pulverize the material preliminarily, a series of pegsin the second zone revoluble about the Vaxis of the pulverizing membersin the first zone and-stationary pegs on the casing associated with therevoluble pegs to pulverize the material finely as it passes inwardlytowards the outlet.

18. pulverizing apparatusC comprising a casing having an inlet and acentrally located outlet on opposite sides thereof, means forming two'pulverizing zones between the inlet and outlet which are connected by anunobstructed annular passage, means includ-` ing yielding, pivotallymounted revoluble members in the iirst zone near the inlet to pulverizethe material preliminarily, and impact members in the second zonebetween said passage and the outlet which revolve rapidly about ahorizontal axis and pulverize the material finely as it passes inwardlytowards the outlet. a

19. In a pulverizing mill having a pulver-` izino' mechanism a ho er afeeding connection from said hopper to said mechanism,

and a discharge conduit, the combination therewith of a mechanicalseparator. in the entrance to said conduit, a gravity separating devicelocated in said conduit and a means to collectV in said gravityseparating device the coarse tailings which pass said mechanicalseparator and to return said tailings' to said hopper..

20. In a pulverizing milly having a casing with a discharge opening, apulverizingmechanism 'including a plurality of rotatable crushingdevices, anda bull ring cooperating with vsaid rotatable devices, thevcombination therewith of a disk rotatable relativeAA to said ring andadjacent said opening, a plurality of pins arranged in concentriccircles on said disk, and additional pins fixed on said casing andalternating with said circles of' movable pins, said pins anddisk actingupon the material after it has passed b8- tween the rotatable crushingdevices and the bull ring and acting to further pulveriz'e towards the Ysaid material. y

l21. A pulverizmg'apparatus comprising a casing having an inlet forcoarse magterial and anl outlet for pulverized material, means formingtwo pulverizing zones adjacent the inlet and outlet respectively,revoluble members in the first zone arranged to preliminarily crushcoarse material, impact menig' bers inthe second zone for producing inepulverization, means for driving the impact i members, and means fordriving the revolu ble members at a diierent speed from that of theimpact members.

In testimony whereof iixed my signature.

Romani s. RILEY,

I 'have hereunto af-

